Conventionally, basal thermometers capable of measuring basal body temperatures of women are known (see, Patent Document 1). Basal body temperatures each show such a biphasic form that a high-temperature phase and a low-temperature phase are periodically repeated, which is caused by a hormonal secretion condition. That is, women can grasp their body conditions resulting from hormonal secretion conditions by regularly taking basal body temperatures. Thus, in recent years, basal body temperature data has been positively used for not only control of pregnancy, contraception, or the like but also health management such as a diet.
On the other hand, to obtain highly reliable basal body temperature data, it is necessary to take a basal body temperature at about the same time every day. Therefore, there is a problem in that highly reliable basal body temperature data cannot be obtained in the case where taking the basal body temperature is forgotten or performed at considerably different times. In view of this, for example, Patent Document 1 discloses a basal thermometer having an alarm function.
Patent Document 1: Japanese Patent Application Laid-open No. HEI10-281891